Furnace-wall construction



Jem 6, 1931. J. E. ANDERsoN 15737334 rummcs WALL consl'xaucl'ron meanov. 1s, 1926 25mn-sheet 14 @gaf Patented Jan. 6, 1931 UNITEDA STATESPATENT OFFICE JOHN E. ANDERSON, OF CHICAGO, ILLINOIS, ASSIGNOR TOPLIBRICO JOINTLESS FIRE- BRICK COMPANY, OIE` CHICAGO, ILLINOIS, A.GOREORATION F ILLINOIS rUnNAcn-wenr. cons'rnncron Application ledNovember'l, 1926. Serial No. 149,072.

This invention relates to furnace construction, and more particularly toa hollow wall construction for furnaces. Y

.It has been recognized that greater efficiency in operation could beobtained by providing air spaces in the wall construction serving toinsulate, to a certain extent, `the refractory lining of the furnacechamber from the outer retaining wall so as to prevent deterioration ofthe outer wall and also eliminate excessive heat losses byv convectionand radiation. It has generally been considered, however, impossible,from a practical standpoint, to support the refractory lining of thefurnace in spaced relation to the outer retaining wall of the furnacesetting due to the fact that the rate of expansion and contraction ofthe lining is very different from the rate of expansion and contractionof the zo retaining wall. p In ordery that a hollow wall constructionfor furnaces should be practical, it is necessary toprov'ide means forproperly supporting the refractory lining in such manner as to permitexpansion and contraction thereof independently of the outer retainingwall of the setting. This has generally been considered impossible. Ihave found, however, that providing suitable anchoring members it ispossible to construct 3u a hollow wall including arefractory lining orinner wall spaced away from the outer retaining wall and supported insuch manner as to have independent expansionand contraction.` '1 v '35.One of the main objects of the invention the outer wall.v A furtherobject is to pro` vide means for supporting the innerwall in such mannerthat the lower edge of this inner wall can be disposed in properrelation to the f re zone or the grate structure ofthefurnace.,

ing the inner or liningV wall of refractory.

Further objects will appear from the detailed description.

rIn the 4drawings Figure l is a fragmentary vertical sectional viewthrough a furnace wall constructed in accordance with my invention;

Fig. 2 is a fragmentary detail perspective view partly broken away,showing the connection between one of the wall anchors and one of theinner wall or lining supporting and anchor members;

Fig. 3 is a perspective detail, partly broken away, of one of the outeror retaining wall anchors and the connection between the same and one ofthe inner wall or lining holding anchors;

' Fig. 4 is a section taken substantially on line lr-t of Fig. 1;

Fig. 5 is a vertical fragment-ary sectional View through a conventionalform of furnace showing a wall construction in accordance with myinvention, as applied; and

Fig. 6 is a view similar to Fig. 5 of a modified form.

The outer or retaining wall l of the furnace setting is formed of anouter thickness or layer 2 of unvitriied brick such as is commonly usedfor this purpose, and an inner layer or thickness 3 of fire-brick ofknown type. An inner or lining wall 4 of refractory material is disposedin spaced relation to the inner face of wall 1, leaving an air space 5between the two walls. The wall 4 is formed fromrefractory materialwhich, when applied, is in a stilf plastic condition, this materialbeing applied in lumps or chunks which are beaten together by a suitablemallet to forni a monolithic structure completely free of all seams orjoints. This material, as stated, is in a sti' plastic condition so thatthe wall can be erected without a retaining form other than a suitablebacking 6 which defines the outer face of the wall and provides asupport against which the wall is formed, as will be obvious. As thewall 4 is of monolithic construction, it can be supported by suitablemembers from the outer wall l in such manner as to be capable ofindependent expansion and contraction. This is an important feature ofmy invention,

as it is not possible, from a practical standpoint, to support an innerlining Wall from an outer retaining wall for independent expansion andcontraction and in spaced relation thereto, unless the inner wall is ofmonolithic construction. In a wall formed of bricks or tiles ofrefractory material, itis necessary to employ a suitable bondingmateriale-r mortar between` thejoints and this material quicklydisintegrates under the inuence of thehightemperaturesdevelopedin thefurnace with the result that openings are quickly formed through therefractorywall, thus destroyinggto a large extent, its usefulness andcausing, within a comparatively short time, the collapse and consequentdestruction of the wall. Thisis particularly true where the refractoryor inner lining wall is supported from the outer retaining wall inspaced relation thereto, as in applicants construction. Infact, it hasbeen considered impossible heretofore to so support an innerrefractoryor liningwall. c

The `wall 4 is supported by supporting and i anchoring brackets 7 ofsubstantially V-shape formed from a single strip of strap metal bent to-provide an upper horizontal arm8, alower'inclined arm 9 disposed at. anacute langle yto arnrS, anda short horizontal element 10 extending fromthe lower end of arm'9. At the apex of the vbracket 7, the

materiallis bent back upon itself to forman upwardly extending finger1,1 disposed at right angles to arm 9. The arms V8 and 10 extendthroughYsuitable openings 12 provided metal. l

rlheouter end of arm 10 is provided with a transverse slot 13 formed byslitting the metal and turning the same downwardly to form a dependingflange14, the end portion of arm 1() being turned upwardly to form anupwardly extending flangel. Slot 13 rein the backing 6, which isvpreferably of sheet ceives the inner end arm 16A of a U-shape anchor 16whichv is anchored in wall l, as illustrated. The outer vend of arm 8 issimilarly secured to the outerwall. The brackety or member 7 isthussecured to the outerl wall` in such manner as'to be capable ofsupporting a great weight `while permitting independent expansion andcontraction of the inner wall 4 Vdue to therelative vertical andtransverse movement between the arm of member 7 and the anchor members16,*slot 18V being of greater Ywidth than arm 16A, as illustra-ted in fFigure 2. The members l7, due to their truss construction, possess greatStrength @millor this reason are employed aS vhangers or supportingmembers for `carrying' the weightof g ce . limited byy headers -17 inthe form of bricks the wall 4 and supporting the same from Wall 1.Movement of wall 4 towards wall 1 is extending from the inner layeriB ofwall 1, theseheaders contacting with the inner face ofthe sheet metalbacking ,6 and kforming abutment elements for the outer face of wall 4.Holding anchor members 17a of elongated U-shape arel imbedded in wall 4and extend through openings 18 in the backing 6. Themember 17a isprovided, adjacent its outerend, with a transverse slot 18k and flanges19 and 20. This slot receives arm 16A` of the outer wall anchor 16,member 17 a beingthus connected to anchor 16Y in the same ymanner as thearms. of` member 7 are Vconnected to their respective anchors. The

123,825; and the particular construction-of the member 7 and associatedanchors 16 and the connections between the same are disclosed' in detailin my copending application for kiiexible anchor filed November 1,41926, Serial No. 145,466. x Y

In practice, the wall 4 is of proper height to suit the particularfurnace and conditions ofk use thereof. f The positionof the bottom oflwall 4 will also bevaried to suit the circumstances.l In Figs. 5 and 6,I have illustrated a conventional form offurnace construction showingthe wall 4 as extending ,below the grate 21. In F ig. 5, the air spacev5 is open at its lower end thus permitting the relatively cool airwhich enters beneath the grate to flow upwardly through space 5, this:air being heated to a certain extent from the refractorylining wall 4land* the'passage of 'the' air upwardly through the spacesl 5 eectuallypreventing heating of the retaining wall 1. In the-modified formillustrated in Fig. 6, the :lower ends of the air spaces 5A are closedby flanges 4A formed at the lower ends of the walls .4. This providesdead air spaces between the inner-and the outer walls which serve toeifectually insulate the same andprevent heating toY any appreciableextent ofthe outerY retaining walls'. In other types lof furnaces inwhich grate structures are not employed, as in furnaces using oil or gasfor fuel, the yposition of the 'lo-wer ends ofthe Vlining `wa'lfls andthe Vheight .of these walls will be varied to suit conditions, as Willbereadily understood by those experi-A enced inthe art. Y f In erectingthe wall 4, suitable strips or' sheets of sheet metal are placed-inposition against thev headers 17; which ser-veto effectually supporttheVbacking 6 thus formed,

these headers doing away with any-necessity rfor employing studding orother means for supporting the. backv 6, :though studdings 'y i may beemployed when desired or necessary,

these studdings being formed of wood and being burned out in the use ofthe furnace. After the walls 4 have been erected in the mannerdescribed, they are suitably dried and 'vitriiied and the furnace isthen in condition vfor use. In use of the furnace, the sheet metalbacking 6 will eventually become oxidized and will disintegrate, afterwhich the outer face of wall 4 will be in direct contact 'with theheaders 17 What I claim is :-V Y 1. In a furnace construction, an outerretaining wall, an inner refractory lining wall spaced from said outerwall, anchor members secured in the inner wall, and anchor memberssecured in the outer wall and having tongue and slot connections withthe inner wall anchor members for supporting the inner wall in spacedrelation to said outerwall while permitting expansion and contraction ofsaid inner wall in every direction in its plane independently of theouter wall.

2. In a furnace construction, a vertical retaining wall, an innervertical lining wall disposed in spacedy relation to the retaining wall,anchor members in the retaining wall, anchor members in the lining wall,means holding the lining against movement toward the retaining wallwhile permitting freedom of expansion and contraction ofthe lining, andconnections between the retaining wall anchor members and the lininganchor members preventing movement of the lining away from the retainingwall while permitting eX- pansion and contraction of the lining in everydirection in its plane.

3. In a furnace construction, an outer retaining wall, an innerrefractory lining wall n spaced from the outer wall, anchor members p`1y of the outer wall.

embedded in the lining wall, and anchor members embedded in the outerwall and having universal connection with the lining wall' anchormembers, whereby the lining wall is free to expand and contract in everydirection in the plane thereof independent- 4. In a furnaceconstruction, an outer wall,

'a monolithic inner lining wall spaced from the outer wall, anchormembers embedded in the outer wall, anchor members embedded lin theinner wall, and tongue and slot connections between the anchor membersper- Amitting expansion and contraction of the inner wall in everydirection 1n the Plane thereof independently of the outer wall.

In witness whereof, I hereunto subscribe my name this 15th day ofNovember, 1926.

Y JOHN E. ANDERSON.

